Credit cards are now fully accepted and widely used for facilitating purchases on credit of goods and services. The credit card identifies the bearer by name and by the number of his account to which purchases will be charged. The name and account number are represented by raised or embossed letters and numbers on the plastic card. This information is customarily recorded on a sales slip by means of a pressure printing device. Checks on the validity of the credit card, and the entering of the sales information into a computer system, generally have required the sales person to read the embossed information from the card and communicate the information to a central point by telephone or by manually operating a computer terminal keyboard. This results in human errors and delays which contribute to inefficiency and customer dissatisfaction.
There is a clear need for a fast and reliable apparatus for automatically sensing the information on a credit card and communicating the information to a central accounting computer. To this end card readers have been proposed which employ mechanical fingers, or optical beams or focused accoustic waves to sense the raised letters and numbers on the card. Other proposed systems involve credit cards with holograms, or surface corrugations, or magnetic inserts, or holes, or resistors arranged to represent the identifying information.
The most important characteristic of a credit card system is that the reading of information from the card be accurate. A second desirable characteristic is that the cards should be relatively counterfeit proof. A third desirable characteristic may be that the card should contain at least some concealed information known only to the card owner which can be used to verify that the bearer of the card is the legitimate owner of the card. Finally, it is desirable that readout of stored information not require a carefully controlled progressive movement of the card relative to the reading apparatus.